Free online BREP to DAE converter

A visualization, game-engine, 3D-printing, or AR application may require COLLADA .dae instead of a CAD boundary-representation file. Converting makes the model usable in software that reads polygon meshes, but the result is faceted geometry rather than an exact editable CAD solid.

What the BREP format is

BREP means boundary representation: the model is defined by faces, edges, vertices, and the mathematical surfaces that bound a solid or shell. Files with the .brep extension commonly use the Open CASCADE BREP format and are created by Open CASCADE-based applications, FreeCAD, and custom CAD or engineering tools.

BREP is used for precise mechanical parts, tooling, industrial design, and CAD data exchange. Unlike a mesh, it can preserve analytic surfaces such as planes, cylinders, cones, and spheres. The .brep extension is not a universal standard, so a file from one CAD system may require that system or a compatible Open CASCADE reader.

What the DAE format is

DAE is the filename extension for COLLADA, an XML-based format for exchanging polygonal 3D scenes. It can contain meshes, transforms, cameras, lights, materials, textures, and animation references.

DAE is suited to Blender, real-time visualization software, some game and simulation tools, 3D viewers, and applications that do not read CAD topology. It preserves scene-oriented mesh data rather than the exact BREP surfaces and parametric history.

How to actually convert BREP to DAE

Using FreeCAD

1. Install a current FreeCAD version and open the .brep file with File → Open. If the file contains several solids, identify the body or components that should appear in the DAE scene.
2. Switch to the Mesh workbench and select the BREP shape in the tree.
3. Choose Meshes → Create mesh from shape. Set the linear or surface deviation and angular deflection. Use smaller deviation and tighter angular settings for curved or highly detailed parts; use larger values for a smaller file.
4. Select the generated mesh, then choose File → Export. Set the output filename to model.dae and select the COLLADA or DAE file type if FreeCAD presents a format list.
5. Open the exported file in the target application and inspect scale, orientation, normals, materials, and missing components. Export separate meshes when the receiving software needs independently selectable parts.

FreeCAD can also be automated through its Python console after importing the BREP and creating a mesh, but the exact scripting calls vary by FreeCAD release and mesh-export module. The graphical workflow is safer when the input contains multiple solids or assemblies.

Using the built-in online converter

You can convert the file for free on the 101convert.com website without installing software. Upload the BREP file, choose DAE as the output format, start the conversion, and download the generated file. Use a desktop workflow instead for confidential CAD, very large files, or models requiring controlled tessellation settings.

Quality and compatibility limitations

DAE cannot retain BREP faces as exact mathematical surfaces, feature history, sketches, constraints, or editable CAD parameters. Conversion tessellates every surface into triangles, so curved areas may show visible faceting if the deviation or angular tolerance is too large.

For a smaller DAE, reduce mesh density after checking the model at its intended viewing distance. For engineering visualization or close-up rendering, use finer tessellation and verify that the target application can handle the resulting polygon count.

Units and axis conventions can change during export. Check whether the receiving program expects millimeters or meters, and verify the model orientation and scale after import. Textures may not transfer because COLLADA exporters and importers differ in support for embedded images, material definitions, and texture paths.